phpJSO (PHP JavaScript Obfuscator) compresses JavaScripts to one line, sometimes to under 30% of the original size. We have compressed 3000+ line/86KB programs to under 25KB.
It works by removing whitespace and comments, like most obfuscators do. Then it uses a special algorithm to further compress code without losing any functionality. phpJSO is completely safe and doesn''t require you make any changes to your code.